International Letters of Natural Sciences Vol. 59

Abstract: Development of drought tolerant high-yielding varieties is essential because increased areas are subject to drought in the Mekong delta, Vietnam. The purpose of this experiment was developed using IR75499-73-1-B as drought tolerant donor and OMCS2000 as a recipient parent basis of a phenotypic and molecular marker for BC₂F₂ generation. Seven markers (RM219, RM201 RM105, RM23602, RM23877, RM24103 and RM328) were used for a idifying to drought tolerant. Primer RM23877 detected the highest number of lines as homozygous donor alleles (11 lines), followed by RM105 and RM201 (9 lines). The drought gene was introgressed into the new breeding lines. The plant height, number of tillers, and filled grain had positive correlation with yield/hill under drought stress. The lines BC₂F₂-45 and BC₂F₂-54 developed as drought tolerant, and gave high yield. This is an opportunity to improve breeding for high yield and drought tolerant rice varieties in Vietnam.

Abstract: 3-D seismic interpretation and petrophysical analysis of the Osaja Field, Niger Delta, was carried out with aim of carrying out a detailed structural interpretation, reservoir characterization and volumetric estimation of the field. Four wells were correlated across the field to delineate the lithology and establish the continuity of reservoir sand as well as the general stratigraphy of the area. The petrophysical analysis carried out, revealed two sand units that are hydrocarbon bearing reservoirs (Sand_A and Sand_B).The spatial variation of the reservoirs were studied on a field wide scale using seismic interpretation. Time and depth structural maps generated were used to establish the structural architecture/geometry of the prospect area of the field. The depth structure map revealed NE-SW trending anticlinal structures with F₅ and F₆ as faults assisted closures to the reservoir. Furthermore, reservoir parameters such as net pay, water saturation porosity, net-to-gross etc, were derived from the integration of seismic and well log data. The structural interpretation on the 3-D seismic data of the study area revealed a total of seven faults ranging from synthetic to antithetic faults. The petrophysical analysis gave the porosity values of the reservoir Sand_A ranging from 18.1 - 20.3% and reservoir Sand_B ranging from 13.1-14.9% across the reservoir. The permeability values of reservoir Sand_A ranging from 63-540md and reservoir Sand_B ranging from 18-80md hence there is decrease in porosity and permeability of the field with depth.The net-to-gross varies from 22.1% to 22.4% in Rerservoir Sand A to between 5.34- 12% for Rerservoir Sand _A while Sw values for the reservoirs ranges from 38-42% in well 2 to about 68.79-96.06% in well 11. The result of original oil in place for all the wells calculated revealed that well 2 has the highest value with 9.3mmbls. These results indicate that the reservoirs under consideration have a poor to fair hydrocarbon (oil) prospect.

Abstract: This research was conducted to study pollen quality in woody plants in the city parks of Dnipro, which are located at various distances from the sources of anthropogenic pollution. It has been revealed that sterile pollen in its greatest abundance was present in plant species in the Park of Memory and Reconciliation and Molodyozhny park, as both are situated within the range of emission transfer from the Western Industrial Complex, while the least abundant sterile pollen was detected in the park named after Yu. Gagarin and that named after V. Dubinin. According to sterility indices, the pollen in Betula pendula Roth. and that in Acer platanoides L. were most sensitive to environmental pollution. In the city parks, the amounts of shrunk and abnormally shaped pollen grains increases; giant forms with grain diameters exceeding standard, as well as dwarf forms are not rare in occurrence. The highest percentage of pollen grains of atypical shape and size was observed in the same parks where the pollen sterility index had its highest values.

Abstract: In order to estimate plant available fraction of metals in two soil samples-contaminated soil (A) and non-contaminated soil (B), a vegetable crop, Curcubita ficifolia was grown on both soil samples. The matured leaf was harvested and analyzed for its metal concentration after three (3) months of growth. The soil samples were collected before and after planting, digested with acid and analyzed to determine the pseudo total metal concentration and quantification was done using atomic absorption spectroscopy (AAS). To correlate metal accumulation by the vegetable with potential bioavailability of metals in soils, sequential extraction (SE) using the modified BCR technique was performed on the soils. Soil sample B was used for quality control. It was observed that each metal differed considerably in uptake. And the C. ficifolia cultivated on soil sample A had tissue concentrations of Zn, Mn and Cu as follows: 39.6mgkg^-1, 18.3mgkg^-1and 26.3mgkg^-1 respectively. Also, C. ficifolia cultivated on soil sample B had a lower absorption of Zn, Mn and Cu with concentrations of 10.21mgkg^-1, 9.11mgkg^-1, and 7.6mgkg^-1 respectively. Results of sequential extraction showed that Zn for soil sample A, and Fe for sample B were mostly present in the acid exchangeable and reducible fractions where these metals were mostly taken up.

Abstract: The purpose of study was conducted to examine factors that influence on germination of Monochoria vaginalis, a major and problematic weed in paddy fields. It was found that seed coats of barnyardgrass and Monochoria itself strongly promoted germination of Monochoria seeds. Germinating rice seeds caused germination induction of Monochoria, but dehulled rice and rice hulls did not play a role. In general, rice root exudates from 2 to 22 day after germination did not exert significant influence on germination and initial growth of Monochoria. The increase of rice seeds showed no remarkable impact on germination, root length and shoot length of Monochoria. In conclusion, it is suggested that coats of weed seeds, residues of rice and other plants in paddy fields may play a critical role in promoting germination of Monochoria seeds. Therefore, the incorporation of these residues in paddy fields may provide negative impact to weed control as germination of Monochoria is much accelerated.

Abstract: Biodeterioration of indoor wood and microbial pollution inside buildings is one of important problem in humid areas. Number of fungi are associated with indoor wood and many of them are responsible for its deterioration by causing decay and stain. Some of them may release mycotoxins, which have hazardous impact on human health. In present study, fifteen fungi associated with wood surface were isolated and out of which genus Aspergillus dominate with four species. A. flavus was recorded from all locations. The potential of leaf extracts of nine tree species on the growth of A. flavus was evaluated by amending culture media. Considerable growth inhibition of A. flavus in the range of 1.14-45.45% was recorded on solid media and 9.37-86.66% in liquid media. Amendment of culture media @ 30% concentration of the leaf extract of Corymbia torelliana have recorded maximum growth inhibition irrespective of the media used.

Abstract: The paper examines the influence of industrial emissions of sulphur (IV) and nitrogen (IV) oxides on stem histological parameters of the autochthonous woody plant species undergrowth of Acer platanoides L. and Fraxinus excelsior L., which are natural forest edificators in the steppe zone of Ukraine. It shows that stem anatomical characteristics undergo quantitative changes in the annual undergrowth shoots of the two tree species under anthropogenic burden, with the most significant changes in the area of heavy pollution. Results indicate the decrease of such stem parameters as stem and stele diameters, wood radius and primary cortex thickness under high concentrations of SO₂ and NO₂ in seedlings of both species. However, this parameter drops in A. platanoides stems by reducing the collenchyme width, whereas it reduces in F. excelsior stems due to cork thickness loss. Another difference in the response of A. platanoides to the influence of phytotoxic pollutants compared to F. excelsior is the depletion of conducting elements of its phloem, which results in thinning the stem secondary cortex. The research findings prove high vulnerability of A. platanoides undergrowth to the chronic SO₂ and NO₂ exposure. Therefore, this woody species is suggested to be used as a test object in monitoring research on plants of virginal group in the technogenic areas contaminated with sulphur (IV) and nitrogen (IV) oxides.

Abstract: In this study, total 41 Vietnamese rice landraces were evaluated for their salt tolerance in the laboratory and field conditions. Amongst them, 15 landraces have shown moderate to high salinity tolerance in both screening conditions. The three landraces Chanh trui, Cuom dang 2 and Nep cuc have revealed the highest salt tolerance which were similar to the Pokkali. However, with time and levels of salt treatments, salt injury symptoms were clearly observed in all landraces with different symptoms. All plants growth parameters were remarkably reduced in all landraces under increasing salt-treated concentrations. By use of molecular marker RM217 linked with salinity tolerance QTL located on the chromosome 4, 11 landraces have been found to carry the allen involving in salt tolerance. This study has provided useful information on salinity tolerance of rice landraces for breeding programs to deal with the climate change in this country.

Abstract: This study investigated the ability of Penicillium sp. to bio-remediate spent engine oil contaminated soil both in vitro and in vivo. In the in vitro assay, mycelium of a seven day old culture of Penicillium sp. grown on Sabouraud Dextrose Agar (SDA) was punched out using a 0.5mm Cork borer and inoculated on the centre of Petri dishes containing the spent and unspent engine oil and incubated for seven days and daily reading of the mycelia growth obtained using a metre rule. For the in vivo assay, soil received 0 (control), 20/180, 40/360, 60/540, 80/720 and 100ml/900mm concentrations/treatments (inoculation with mycelium of Penicillium sp.). Seeds of Telfeira occidentalis was sown on the soil and assessed for growth performance (plant height, leaf area (using a metre rule) and leaf count (number of leaves) for 7, 14, 21 and 28 Days after Planting (DAP). Results of the in vitro assay showed a significant increase (p<0.05) in the growth diameter of Penicillium sp. relative to control. Results of the in vivo assay showed that spent engine oil had no significant effect (p<0.05) on the growth performance of T. occidentalis at 7, 14, 21 and 28 DAP and on fresh and dry weight (g) 28 DAP relative to control. After 28 days of plant growth, the added spent engine oil was no longer detected. The plant began producing pods 61 DAP. This study showed that Penicillium sp. can biodegrade hydrocarbons present in spent engine oil and as such is a good tool for bioremediation.